Neuromodulation continues to increase as an adopted technique for treating of a wide variety of medical conditions. For example, neuromodulation devices for spinal cord stimulation have been utilized for the management of pain. Similarly, neuromodulation devices for deep brain stimulation have been utilized for the treatment of Parkinson's, essential tremor, dystonia, and other disorders. Neuromodulation devices for vagus nerve stimulation have been utilized to control seizures, such as those associated with epilepsy. Also, neuromodulation devices for renal nerve stimulation have been utilized to control blood pressure.
Existing neuromodulation systems typically require a surgical procedure to implant one or more electrodes at a desired location within a patient. Conductors then lead from the electrodes to a power source and pulse generator. The power source, such as a battery, can be implanted along with the electrodes. However, if the power source becomes disconnected, stops holding a charge, or otherwise stops working properly, a further surgery is required to replace the power source. To eliminate this issue, the conductors may lead from the electrodes to a power source positioned outside of the body. However, this approach requires an opening through the skin that can be uncomfortable for the patient, prone to infection, and prone to causing scar tissue along the length of the conductors within the patient. Further, the longer the distance the conductors have to extend between the power source and the electrodes, the greater the amount of power that is required to be provided to account for the increased attenuation of the electrical signal along the length of thin conductors, which are preferred or, in some cases, required for patient comfort and/or access to the desired stimulation site. Also, the electrode leads need to be tethered to the power source and pulse generator and restrain its movement with the intrinsic twitching of muscles, motion of various body parts, and different postures (e.g., between lying down and standing up) that cause the stimulating leads to move, cause undue stress, and/or de-tethering. The very high difference between the elasticity of human tissue and the constrained electrode lead(s) can also cause addition scaring.
As a result, there is a need for improved devices, systems, and methods for electrically stimulating nerves and/or monitoring nerve activity.